Project Summary/Abstract: We propose to purchase an advanced, versatile 3D printer (the Stratasys J750) to facilitate research activities within multiple groups at the Rehabilitation Institute of Chicago (RIC)?the largest rehabilitation research facility in the world. This machine, which will rapidly become an integral part of the RIC research infrastructure, will facilitate design innovation, enhance productivity per research dollar, and enable manufacture of custom parts and improved interfaces for human subjects research. Our long-term objective is to enhance the understanding and treatment of diseases and injuries that affect human ability. RIC research focuses on development of novel technologies to understand and treat a diverse array of conditions including stroke, amputation, traumatic brain injury, and spinal cord injury. RIC researchers are leaders in diverse areas of rehabilitation engineering and collaborate extensively, both nationally and internationally, within their fields; a unique aspect of RIC research is the close collaboration between researchers, clinicians, and individuals with disability. The J750 printer will be used by several RIC research groups to facilitate iterative design and innovation, and to develop novel equipment for research or therapy. The instrument will be available to researchers and clinicians within RIC on an at-cost basis (taking into account materials used). The ability to create these products at RIC (instead of, as is currently necessary, outsourcing jobs to 3D printing facilities) will substantially reduce costs and turnaround time, which will enable faster research progress; more cycles of design optimization and testing for a given research budget; and innovation?rapid testing of new ideas that may lead to new areas of research. The ability to optimize device design through engineering and iterative testing in appropriate patient groups will be an invaluable addition to RIC research. The instrument will also enable production of custom parts and appliances for individual research subjects, which is currently prohibited by cost and time. Devices that fit better and are more comfortable will enable more precise biomechanical studies. Technology that works ergonomically and biomechanically with the patient is more likely to be successfully integrated into rehabilitation protocols, and is likely to be of greater benefit to the intended user. The unique features of this state-of-the-art machine, including the ability to print a wide variety of different materials with diverse material properties (e.g., soft or hard surfaces) within a single device, will allow us to improve human-robot interfaces to enhance user comfort and safety. Given the many diverse areas of research at the RIC, this versatile 3D printer will contribute to advances in several fields of rehabilitation engineering and research.